Now when you build your user.link object, the display_order param will be set too.

网友答案:

Alter your schema so it has a display_order column or something similar, and have this pushed through as a hidden input on the front end.

Relying on the id column for ordering is discouraged, as it is essentially an arbitrary value created by the DB, which happens to follow a logical sequence most of the time. Having a separate column for the order won't break DRYness because it is (technically) for a different purpose.